Physical properties are those which can be observed without any change in composition of the substance. Hence, a is the answer.
Concave is not a type of mechanical wave because it doesn’t need a medium for propagation.
The chemical formula C₂H₆O, which is designated as option D, is equivalent to this structural formula.
<h3><u>What is a Chemical Formula ?</u></h3>
Chemical element symbols, numbers, and occasionally additional symbols like parentheses, dashes, brackets, commas, and plus (+) and minus () signs are used in a chemical formula to represent information about the chemical proportions of the atoms that make up a certain chemical compound or molecule.
- An empirical formula represents by symbols, such as Na for sodium and Cl for chlorine, with subscripts that show the relative number of atoms in each.
- The composition of any member of an entire class of compounds can be represented by a general formula, a sort of empirical formula.
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